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371.
麦类籽实中植酸酶的活性及体外降解植酸盐效果的研究   总被引:1,自引:0,他引:1  
为评价不同麦类籽实中内源植酸酶的活性及其对外源植酸盐的降解能力,以植酸钠为底物,测定5种10个不同品种麦类籽实中植酸酶的活性;在37℃、pH 5.50的条件下,以300 U/kg的浓度加入从麦类籽实中提取的植酸酶,检测了对玉米、豆粕中植酸磷的释放效果。结果表明,燕麦、大麦(垦啤2号)、小麦(东农123)、小麦(东农973821)、小黑麦(5305)、小黑麦(92021)、小黑麦(96026)、小黑麦(8809)、胜利黑麦和黑麦(2号)籽实中植酸酶的活性分别为57.50、143.25、1048.06、725.22、1978.67、2201.65、1713.46、1406.49、5310.89 U/kg和3446.53 U/kg(风干基础);在上述条件下,反应8h,玉米、豆粕中的植酸磷分别释放71.92%和38.94%。  相似文献   
372.
外源植酸酶对土壤磷酸酶活性和有效磷含量的影响   总被引:1,自引:1,他引:0  
采用室内培养的方法,研究了不同用量外源植酸酶在不同培养时期对土壤磷酸酶活性和有效磷含量的影响.结果表明,添加外源植酸酶各处理的土壤酸性、中性磷酸酶活性和有效磷含量均高于对照,各处理间呈高量>中量>低量>对照,其中土壤酸性、中性磷酸酶活性与对照相比增加的幅度分别为9.3%~70.2%、4.3%~73.1%,差异达显著水平;从培养时间来看,土壤磷酸酶活性和有效磷含量均随培养时间的延长呈先升高后略有回落的趋势,其中酸性磷酸酶活性至培养第10 d达最高值,此时各处理与对照相比提高了33.9%~70.2%,差异达极显著水平,而中性磷酸酶活性和有效磷含量至培养的第20 d达到最高值,此时与对照相比分别提高了49.9%~73.1%和26.6%~122.5%.  相似文献   
373.
【目的】 黄淮海地区夏玉米生长季多雨寡照频发,同时生产上种植密度的增加影响了群体光照,研究植酶Q9对大田遮阴夏玉米生长发育和产量的调控作用具有重要意义。【方法】 2013—2018年,在大田条件下选用夏玉米品种登海605为试验材料,种植密度67 500株/hm 2。试验设置3个遮阴处理,分别为开花至收获期遮阴(S1)、拔节至开花期遮阴(S2)和出苗至收获期遮阴(S3),以自然光照为对照(CK),大田遮光率为60%;另外,选用化控试剂植酶Q9对遮阴和正常光照处理进行外源调控,即开花至收获期遮阴-植酶Q9(Z-S1)、拔节至开花期遮阴-植酶Q9(Z-S2)、出苗至收获期遮阴-植酶Q9(Z-S3)和正常光照-植酶Q9(Z-CK),以同时期喷施清水为对照,探讨植酶Q9对大田遮阴夏玉米产量形成的影响【结果】 遮阴延缓夏玉米的生长发育进程,雌雄间隔延长,抽雄和吐丝期较对照延迟6 d左右,叶面积指数、功能叶片SPAD值、干物质积累量显著降低,穗长、穗粗减小,秃顶变长,株高、穗位高降低,倒伏率和空秆率增加,进而产量显著降低。喷施植酶Q9后,S3和S2的生育进程较其对照提前1—2 d,雌雄间隔缩短1 d,叶面积指数、SPAD值、穗位高、株高显著增加;干物质积累及其向籽粒的分配比例增加,倒伏率和空秆率降低;S3穗部性状得到改善。喷施植酶Q9增加了夏玉米的公顷穗数、穗粒数、千粒重,进而显著提高产量,S3、S2、S1喷施植酶Q9后分别平均增产21%、9%、14%。【结论】 喷施植酶Q9可以有效缓解夏玉米弱光胁迫导致的危害。  相似文献   
374.
采用单因素随机区组设计的方法,选择二元杂交(长白×大约克)28日龄断奶仔猪40头,平均断奶体重(7.5±0.5)kg,研究玉米豆粕型日粮添加植酸酶(300U/kg)对断奶仔猪生产性能、养分消化率及血清生化指标的影响。结果表明,玉米豆粕型日粮中添加植酸酶降低了断奶仔猪的采食量(-9.8%P<0.06),猪的日增重下降11.1%(428与383g/d),但差异不显著(P>0.05),对饲料效率影响不显著(P>0.05)。断奶仔猪日粮中添加植酸酶,提高了日粮中干物质、能量、蛋白质、钙和磷的消化率:3.4%P>0.05、2.6%P>0.05、2.8%P>0.05、14.5%P<0.05和4.8%P<0.12,改善了氨基酸回肠表观消化率:His+11.7%、Ile+2.7%、Leu+6.2%、Lys+5.4%、Met+1.1%,但差异不显著(P>0.05)。断奶仔猪日粮中添加植酸酶,降低了42天血清中的葡萄糖、血清尿素氮和血清碱性磷酸酶水平,分别降低15.2%P<0.07、22.2%P<0.12、29.5%P<0.05。提高了断奶仔猪42天的血清T3、T4和胰岛素水平,分别提高15.6%P>0.05、4.4%P>0.05和10.9%P>0.05。综上所述,断奶仔猪日粮中添加植酸酶提高断奶仔猪营养物质回肠表观消化率,改善了营养物质的吸收与利用,并由此改变了机体中生化代谢和基础代谢。  相似文献   
375.
从海南洋浦近海分离到1株产植酸酶的酵母菌株,经鉴定为热带假丝酵母(Candida tropicalis),利用Plackett-Burman设计对其发酵条件进行了筛选。结果表明,豌豆粉浓度、硫酸铵浓度和初始pH对酶产量具有显著的影响;利用响应面法对3个因子进行了优化,获得了最佳发酵条件:豌豆粉1.0%,葡萄糖2.0%,硫酸铵1.7%,氯化钠1.0%,初始pH 5.2,培养72 h,植酸酶产量达到727.5 U/mL。  相似文献   
376.
Two experiments were conducted to investigate the effect of dietary supplementation with phytase transgenic corn (PTC)on growth performance, phosphorus (P) utilization and excretion in growing pigs. In Exp. 1, 180 pigs (Large White ×Landrace, BW=37.7 kg) were randomly allotted to 4 treatments with 5 replicates of 9 pigs each in order to evaluate the effect of PTC supplementation in low-P diets on growth performance. Four corn soybean meal-based diets consisted of a positive control (PC) diet, a diet containing 500 units (U) of exogenous phytase kg-1 (EP) on the basis of low-P (inorganic P reduced by 0.05% from PC diet) and the low-P+500 (PTC1) or 750 (PTC2) phytase U ofPTC kg-1. In Exp. 2, 20 barrows (Large White×Landrace, BW=31 kg, 4 treatments with 5 replicates of 1 pig each) were randomly selected to evaluate the effect of PTC in low-P diets on serum parameters and nutrient utilization. Diets in Exp. 2 were similar to those in Exp. 1except that the EP group was replaced by a low-P diet without exogenous phytase supplementation as a negative control (NC) group. The results from Exp. 1 showed that the average daily gain (ADG) in the PTC2 group was significantly higher (P<0.05) than that in the EP group over all periods. On the other hand, the feed:gain (F:G) ratio of the EP group was significantly higher (P<0.05) than that of the PTC2 group during 1-21 and 1-42 d, respectively. There were no differences in average daily feed intake (ADFI) among all treatments (P>0.05). The results from Exp. 2 showed that the concentration of serum Ca in the NC group was the highest (P<0.05), while the concentration of serum P in the PTC2 group was the highest (P<0.05) among all treatments. There was a significant decrease (P<0.05) in the P apparent digestibility of the NC group compared with the other groups, and that of PTC2 group was the best. Furthermore, fecal P excretion was reduced (P<0.05) from 1.80 g d-1 in the PC group to 1.28 g d-1 in the PTC2 group. In conclusion, dietary supplementation with PTC could reduce the application of inorganic P, decrease fecal P excretion, and improve the growth performance of growing pigs.  相似文献   
377.
【目的】探讨在仔猪颗粒料中添加植酸酶对仔猪生产性能与血液生化指标的影响。【方法】将224头杜洛克×长白×大约克三元杂交仔猪随机分为对照组和试验A、B、C组,对照组饲喂颗粒料(制粒温度为83℃),试验A、B、C组分别饲喂以粉状、颗粒状和液体植酸酶代替1/2磷酸氢钙(另1/2磷酸氢钙用石粉和载体代替)的颗粒料,酶的添加量为100 g/t或100 m/t,试验期为30 d。试验前后分别测定生产性能和血液生化指标。【结果】与对照组比较,B和C组平均日增重分别提高5.30%和6.14%(P<0.05),料重比分别降低3.08%和4.10%(P<0.05),白蛋白含量分别提高17.05%和21.38%(P<0.05),球蛋白含量分别提高18.81%和23.73%(P<0.05),总蛋白含量分别提高9.94%和15.81%(P<0.05),碱性磷酸酶、总胆固醇、丙氨酸氨基转移酶、天门冬氨酸氨基转移酶、血红蛋白、血清钙和血清磷等含量较对照均有所增加,但差异不显著(P>0.05);试验A组与对照组各项指标差异均不显著(P>0.05)。【结论】在制粒温度不超过83℃时,仔猪颗粒料中添加颗粒型和液体型植酸酶,可提高仔猪的生产性能和血液生化指标。  相似文献   
378.
转基因水稻中重组植酸酶的表达   总被引:5,自引:0,他引:5  
为通过在转基因植株中表达植酸酶降解植酸来提高水稻中无机磷利用率,构建了由玉米泛素基因Ubi启动子控制的植酸酶基因植物表达载体,并以来源于水稻未成熟胚的愈伤组织作为转化受体,经农杆菌介导法将植酸酶基因导入水稻中,共获得15个独立的转基因株系。对转基因水稻总DNA的PCR和Southern 杂交分析证明目的基因已整合入转基因水稻植株基因组中,并能稳定遗传。对部分转基因水稻未成熟种子总RNA进行RT PCR分析,表明导入的植酸酶基因能够在转基因水稻种子中正常表达。无机磷含量分析表明含目的基因的转基因水稻种子及其后代叶片中的无机磷含量较未转化植株均有了明显的提高。  相似文献   
379.
Six isonitrogenous (320 g kg?1) and isolipidic (60 g kg?1) diets were formulated with graded levels (0, 5, 10 and 15 g kg?1) of dicalcium phosphate (DCP) and fungal phytase (750 and 1500 FTU kg?1 diet). Tra catfish (Pangasianodon hypophthalmus), 9.6 g, were fed the diets for 12 weeks. Each experimental diet was fed to eight replicates of fish to apparent satiation. At the end of the trial, fish fed the diets containing 15 g kg?1 DCP, 750 and 1500 FTU kg?1 phytase had higher growth performances, protein efficiency ratio and phosphorus retention than those fed the control diet, 5 g kg?1 DCP and 10 g kg?1 DCP diets (P < 0.05). Whole body ash and phosphorus concentration of fish fed the 10 g kg?1 DCP and 15 g kg?1 DCP diets were significantly higher than those of fish fed the control diet. Higher apparent digestibility coefficient of phosphorus was observed in fish fed the phytase supplemented diets. The present results indicate that supplementation of phytase at 750 FTU kg?1 and 1500 FTU kg?1 improves growth performances, feed and phosphorus utilization. The supplementation can completely replace dicalcium phosphate or other phosphorus sources in tra catfish feed and reduce the phosphorus discharge into environment.  相似文献   
380.
This study investigated the effects of fermentation product containing phytase (FPP) that was fermented using waste vinegar residue (WVR) as substrate from Aspergillusficuum NTG-23 on productive performance, egg quality, and phosphorus apparent metabolism of laying hens. First, 375 22-wk-old Jinghong hens were allocated into 5 treatments (5 replicates of 15 hens each) in an 8-wk experiment for evaluating the parameters of productive performance, egg quality, serum, and tibia. Experimental diets contained 4% FPP and 96% corn-soybean diet. The levels of dicalciurn phosphate (DCP) were 1.34, 1.01, 0.67, 0.34 and 0%. Next, thirty 31-wk-old Jinghong hens were fed 5 types of diets for evaluating phosphorous apparent metabolism rate. Egg productive rate, egg weight, feed conversion ratio, Haugh unit, egg albumen height, serum calcium, tibia ash, tibia ash calcium and tibia breaking strength were not different significantly among 5 treatments. The significant difference of average daily feed intake was not appeared when the DCP content of corn-soybean-FPP diet was reduced to 0.67%; the eggshell hardness, eggshell thickness and serum phosphorus were not reduced significantly until the DCP content of corn-soybean-FPP diet was reduced to 0.34%. The yolk color was improved when the laying hens fed deficient DCP corn-soybean-FPP diet. A 22.14% reduction in excreta phosphorus was observed when the laying hens fed low phosphorus (0.67% DCP) corn-soybean-FPP diet. A 30% elevation of phosphorus apparent metabolism rate was obtained when the DCP content of corn-soybean-FPP diet was decreased from 1.34 to 1.01%. The reducing cost of layer diet was totalized about 120 CNY 1000 kg1 diet when the content of DCP was 0.67% in corn-soybean-FPP diet. These results indicated that FPP could be applied in laying hen as a potential, cost-effective and rational application of WVR.  相似文献   
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